1. 05 5月, 2013 1 次提交
  2. 01 5月, 2013 2 次提交
    • T
      dump_stack: unify debug information printed by show_regs() · a43cb95d
      Tejun Heo 提交于
      show_regs() is inherently arch-dependent but it does make sense to print
      generic debug information and some archs already do albeit in slightly
      different forms.  This patch introduces a generic function to print debug
      information from show_regs() so that different archs print out the same
      information and it's much easier to modify what's printed.
      
      show_regs_print_info() prints out the same debug info as dump_stack()
      does plus task and thread_info pointers.
      
      * Archs which didn't print debug info now do.
      
        alpha, arc, blackfin, c6x, cris, frv, h8300, hexagon, ia64, m32r,
        metag, microblaze, mn10300, openrisc, parisc, score, sh64, sparc,
        um, xtensa
      
      * Already prints debug info.  Replaced with show_regs_print_info().
        The printed information is superset of what used to be there.
      
        arm, arm64, avr32, mips, powerpc, sh32, tile, unicore32, x86
      
      * s390 is special in that it used to print arch-specific information
        along with generic debug info.  Heiko and Martin think that the
        arch-specific extra isn't worth keeping s390 specfic implementation.
        Converted to use the generic version.
      
      Note that now all archs print the debug info before actual register
      dumps.
      
      An example BUG() dump follows.
      
       kernel BUG at /work/os/work/kernel/workqueue.c:4841!
       invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
       Modules linked in:
       CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #7
       Hardware name: empty empty/S3992, BIOS 080011  10/26/2007
       task: ffff88007c85e040 ti: ffff88007c860000 task.ti: ffff88007c860000
       RIP: 0010:[<ffffffff8234a07e>]  [<ffffffff8234a07e>] init_workqueues+0x4/0x6
       RSP: 0000:ffff88007c861ec8  EFLAGS: 00010246
       RAX: ffff88007c861fd8 RBX: ffffffff824466a8 RCX: 0000000000000001
       RDX: 0000000000000046 RSI: 0000000000000001 RDI: ffffffff8234a07a
       RBP: ffff88007c861ec8 R08: 0000000000000000 R09: 0000000000000000
       R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8234a07a
       R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
       FS:  0000000000000000(0000) GS:ffff88007dc00000(0000) knlGS:0000000000000000
       CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
       CR2: ffff88015f7ff000 CR3: 00000000021f1000 CR4: 00000000000007f0
       DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
       DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
       Stack:
        ffff88007c861ef8 ffffffff81000312 ffffffff824466a8 ffff88007c85e650
        0000000000000003 0000000000000000 ffff88007c861f38 ffffffff82335e5d
        ffff88007c862080 ffffffff8223d8c0 ffff88007c862080 ffffffff81c47760
       Call Trace:
        [<ffffffff81000312>] do_one_initcall+0x122/0x170
        [<ffffffff82335e5d>] kernel_init_freeable+0x9b/0x1c8
        [<ffffffff81c47760>] ? rest_init+0x140/0x140
        [<ffffffff81c4776e>] kernel_init+0xe/0xf0
        [<ffffffff81c6be9c>] ret_from_fork+0x7c/0xb0
        [<ffffffff81c47760>] ? rest_init+0x140/0x140
        ...
      
      v2: Typo fix in x86-32.
      
      v3: CPU number dropped from show_regs_print_info() as
          dump_stack_print_info() has been updated to print it.  s390
          specific implementation dropped as requested by s390 maintainers.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Acked-by: NDavid S. Miller <davem@davemloft.net>
      Acked-by: NJesper Nilsson <jesper.nilsson@axis.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Bjorn Helgaas <bhelgaas@google.com>
      Cc: Fengguang Wu <fengguang.wu@intel.com>
      Cc: Mike Frysinger <vapier@gentoo.org>
      Cc: Vineet Gupta <vgupta@synopsys.com>
      Cc: Sam Ravnborg <sam@ravnborg.org>
      Acked-by: Chris Metcalf <cmetcalf@tilera.com>		[tile bits]
      Acked-by: Richard Kuo <rkuo@codeaurora.org>		[hexagon bits]
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      a43cb95d
    • T
      dump_stack: consolidate dump_stack() implementations and unify their behaviors · 196779b9
      Tejun Heo 提交于
      Both dump_stack() and show_stack() are currently implemented by each
      architecture.  show_stack(NULL, NULL) dumps the backtrace for the
      current task as does dump_stack().  On some archs, dump_stack() prints
      extra information - pid, utsname and so on - in addition to the
      backtrace while the two are identical on other archs.
      
      The usages in arch-independent code of the two functions indicate
      show_stack(NULL, NULL) should print out bare backtrace while
      dump_stack() is used for debugging purposes when something went wrong,
      so it does make sense to print additional information on the task which
      triggered dump_stack().
      
      There's no reason to require archs to implement two separate but mostly
      identical functions.  It leads to unnecessary subtle information.
      
      This patch expands the dummy fallback dump_stack() implementation in
      lib/dump_stack.c such that it prints out debug information (taken from
      x86) and invokes show_stack(NULL, NULL) and drops arch-specific
      dump_stack() implementations in all archs except blackfin.  Blackfin's
      dump_stack() does something wonky that I don't understand.
      
      Debug information can be printed separately by calling
      dump_stack_print_info() so that arch-specific dump_stack()
      implementation can still emit the same debug information.  This is used
      in blackfin.
      
      This patch brings the following behavior changes.
      
      * On some archs, an extra level in backtrace for show_stack() could be
        printed.  This is because the top frame was determined in
        dump_stack() on those archs while generic dump_stack() can't do that
        reliably.  It can be compensated by inlining dump_stack() but not
        sure whether that'd be necessary.
      
      * Most archs didn't use to print debug info on dump_stack().  They do
        now.
      
      An example WARN dump follows.
      
       WARNING: at kernel/workqueue.c:4841 init_workqueues+0x35/0x505()
       Hardware name: empty
       Modules linked in:
       CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #9
        0000000000000009 ffff88007c861e08 ffffffff81c614dc ffff88007c861e48
        ffffffff8108f50f ffffffff82228240 0000000000000040 ffffffff8234a03c
        0000000000000000 0000000000000000 0000000000000000 ffff88007c861e58
       Call Trace:
        [<ffffffff81c614dc>] dump_stack+0x19/0x1b
        [<ffffffff8108f50f>] warn_slowpath_common+0x7f/0xc0
        [<ffffffff8108f56a>] warn_slowpath_null+0x1a/0x20
        [<ffffffff8234a071>] init_workqueues+0x35/0x505
        ...
      
      v2: CPU number added to the generic debug info as requested by s390
          folks and dropped the s390 specific dump_stack().  This loses %ksp
          from the debug message which the maintainers think isn't important
          enough to keep the s390-specific dump_stack() implementation.
      
          dump_stack_print_info() is moved to kernel/printk.c from
          lib/dump_stack.c.  Because linkage is per objecct file,
          dump_stack_print_info() living in the same lib file as generic
          dump_stack() means that archs which implement custom dump_stack()
          - at this point, only blackfin - can't use dump_stack_print_info()
          as that will bring in the generic version of dump_stack() too.  v1
          The v1 patch broke build on blackfin due to this issue.  The build
          breakage was reported by Fengguang Wu.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Acked-by: NDavid S. Miller <davem@davemloft.net>
      Acked-by: NVineet Gupta <vgupta@synopsys.com>
      Acked-by: NJesper Nilsson <jesper.nilsson@axis.com>
      Acked-by: NVineet Gupta <vgupta@synopsys.com>
      Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>	[s390 bits]
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Mike Frysinger <vapier@gentoo.org>
      Cc: Fengguang Wu <fengguang.wu@intel.com>
      Cc: Bjorn Helgaas <bhelgaas@google.com>
      Cc: Sam Ravnborg <sam@ravnborg.org>
      Acked-by: Richard Kuo <rkuo@codeaurora.org>		[hexagon bits]
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      196779b9
  3. 30 4月, 2013 2 次提交
  4. 17 4月, 2013 1 次提交
  5. 10 4月, 2013 1 次提交
  6. 08 4月, 2013 1 次提交
  7. 01 4月, 2013 1 次提交
    • K
      net: add option to enable error queue packets waking select · 7d4c04fc
      Keller, Jacob E 提交于
      Currently, when a socket receives something on the error queue it only wakes up
      the socket on select if it is in the "read" list, that is the socket has
      something to read. It is useful also to wake the socket if it is in the error
      list, which would enable software to wait on error queue packets without waking
      up for regular data on the socket. The main use case is for receiving
      timestamped transmit packets which return the timestamp to the socket via the
      error queue. This enables an application to select on the socket for the error
      queue only instead of for the regular traffic.
      
      -v2-
      * Added the SO_SELECT_ERR_QUEUE socket option to every architechture specific file
      * Modified every socket poll function that checks error queue
      Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
      Cc: Jeffrey Kirsher <jeffrey.t.kirsher@intel.com>
      Cc: Richard Cochran <richardcochran@gmail.com>
      Cc: Matthew Vick <matthew.vick@intel.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      7d4c04fc
  8. 13 3月, 2013 1 次提交
  9. 04 3月, 2013 1 次提交
  10. 28 2月, 2013 1 次提交
  11. 26 2月, 2013 1 次提交
  12. 14 2月, 2013 1 次提交
    • A
      burying unused conditionals · d64008a8
      Al Viro 提交于
      __ARCH_WANT_SYS_RT_SIGACTION,
      __ARCH_WANT_SYS_RT_SIGSUSPEND,
      __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND,
      __ARCH_WANT_COMPAT_SYS_SCHED_RR_GET_INTERVAL - not used anymore
      CONFIG_GENERIC_{SIGALTSTACK,COMPAT_RT_SIG{ACTION,QUEUEINFO,PENDING,PROCMASK}} -
      can be assumed always set.
      d64008a8
  13. 04 2月, 2013 6 次提交
  14. 24 1月, 2013 1 次提交
  15. 17 1月, 2013 1 次提交
    • V
      sk-filter: Add ability to lock a socket filter program · d59577b6
      Vincent Bernat 提交于
      While a privileged program can open a raw socket, attach some
      restrictive filter and drop its privileges (or send the socket to an
      unprivileged program through some Unix socket), the filter can still
      be removed or modified by the unprivileged program. This commit adds a
      socket option to lock the filter (SO_LOCK_FILTER) preventing any
      modification of a socket filter program.
      
      This is similar to OpenBSD BIOCLOCK ioctl on bpf sockets, except even
      root is not allowed change/drop the filter.
      
      The state of the lock can be read with getsockopt(). No error is
      triggered if the state is not changed. -EPERM is returned when a user
      tries to remove the lock or to change/remove the filter while the lock
      is active. The check is done directly in sk_attach_filter() and
      sk_detach_filter() and does not affect only setsockopt() syscall.
      Signed-off-by: NVincent Bernat <bernat@luffy.cx>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      d59577b6
  16. 04 1月, 2013 1 次提交
  17. 20 12月, 2012 4 次提交
  18. 19 12月, 2012 1 次提交
    • F
      h8300: select generic atomic64_t support · d95bfe46
      Fengguang Wu 提交于
      Rationales from Eric:
      
      So I just looked a little deeper and it appears architectures that do
      not support atomic64_t are broken.
      
      The generic atomic64 support came in 2009 to support the perf subsystem
      with the expectation that all architectures would implement atomic64
      support.
      
      Furthermore upon inspection of the kernel atomic64_t is used in a fair
      number of places beyond the performance counters:
      
      block/blk-cgroup.c
      drivers/acpi/apei/
      drivers/block/rbd.c
      drivers/crypto/nx/nx.h
      drivers/gpu/drm/radeon/radeon.h
      drivers/infiniband/hw/ipath/
      drivers/infiniband/hw/qib/
      drivers/staging/octeon/
      fs/xfs/
      include/linux/perf_event.h
      include/net/netfilter/nf_conntrack_acct.h
      kernel/events/
      kernel/trace/
      net/mac80211/key.h
      net/rds/
      
      The block control group, infiniband, xfs, crypto, 802.11, netfilter.
      Nothing quite so fundamental as fs/namespace.c but definitely in
      multiplatform-code that should work, and is already broken on those
      architecutres.
      
      Looking at the implementation of atomic64_add_return in lib/atomic64.c the
      code looks as efficient as these kinds of things get.
      
      Which leads me to the conclusion that we need atomic64 support on all
      architectures.
      Signed-off-by: NFengguang Wu <fengguang.wu@intel.com>
      Cc: "Eric W. Biederman" <ebiederm@xmission.com>
      Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      d95bfe46
  19. 10 12月, 2012 1 次提交
  20. 29 11月, 2012 4 次提交
  21. 14 11月, 2012 1 次提交
  22. 09 11月, 2012 1 次提交
  23. 01 11月, 2012 1 次提交
    • P
      sk-filter: Add ability to get socket filter program (v2) · a8fc9277
      Pavel Emelyanov 提交于
      The SO_ATTACH_FILTER option is set only. I propose to add the get
      ability by using SO_ATTACH_FILTER in getsockopt. To be less
      irritating to eyes the SO_GET_FILTER alias to it is declared. This
      ability is required by checkpoint-restore project to be able to
      save full state of a socket.
      
      There are two issues with getting filter back.
      
      First, kernel modifies the sock_filter->code on filter load, thus in
      order to return the filter element back to user we have to decode it
      into user-visible constants. Fortunately the modification in question
      is interconvertible.
      
      Second, the BPF_S_ALU_DIV_K code modifies the command argument k to
      speed up the run-time division by doing kernel_k = reciprocal(user_k).
      Bad news is that different user_k may result in same kernel_k, so we
      can't get the original user_k back. Good news is that we don't have
      to do it. What we need to is calculate a user2_k so, that
      
        reciprocal(user2_k) == reciprocal(user_k) == kernel_k
      
      i.e. if it's re-loaded back the compiled again value will be exactly
      the same as it was. That said, the user2_k can be calculated like this
      
        user2_k = reciprocal(kernel_k)
      
      with an exception, that if kernel_k == 0, then user2_k == 1.
      
      The optlen argument is treated like this -- when zero, kernel returns
      the amount of sock_fprog elements in filter, otherwise it should be
      large enough for the sock_fprog array.
      
      changes since v1:
      * Declared SO_GET_FILTER in all arch headers
      * Added decode of vlan-tag codes
      Signed-off-by: NPavel Emelyanov <xemul@parallels.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      a8fc9277
  24. 15 10月, 2012 3 次提交
  25. 13 10月, 2012 1 次提交
    • J
      vfs: define struct filename and have getname() return it · 91a27b2a
      Jeff Layton 提交于
      getname() is intended to copy pathname strings from userspace into a
      kernel buffer. The result is just a string in kernel space. It would
      however be quite helpful to be able to attach some ancillary info to
      the string.
      
      For instance, we could attach some audit-related info to reduce the
      amount of audit-related processing needed. When auditing is enabled,
      we could also call getname() on the string more than once and not
      need to recopy it from userspace.
      
      This patchset converts the getname()/putname() interfaces to return
      a struct instead of a string. For now, the struct just tracks the
      string in kernel space and the original userland pointer for it.
      
      Later, we'll add other information to the struct as it becomes
      convenient.
      Signed-off-by: NJeff Layton <jlayton@redhat.com>
      Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      91a27b2a